You can select one of the three color models that will perfectly fit your design:
HEX. Each color is represented by a 6-digit combination of numbers and letters, e.g., #FFFFFF. The most common model in web design, HEX was already built into Tilda.
RGB. The colors are encoded based on the proportions of the primary colors - red, green, and blue, such as 255, 255, 255.
HSL. Color is specified by three parameters: Tone, Saturation, and Lightness, such as 11, 0%, 100%. This model is designed according to human color perception (not the machine one).